Place the sliced potatoes into a greased 9x13" baking pan and sprinkle the salt over them. Toss to coat and preheat the oven to 375°F. In a small saucepan, place the remaining ingredients except for the vanilla over medium-high heat and stir until the butter has melted and its come to a low boil.

Let it boil, undisturbed, for 2 minutes, then remove it from the heat, stir in the vanilla and pour it evenly over the potatoes. Give them a toss, then place them into the oven for a total time of 1 hour. After the first 20 minutes, take them out, give them a stir and cover the pan with foil for the remaining baking time. Take them out to stir again at the 40 minute mark.

Once the hour is up, the potatoes should be very tender. The sauce will seem very thin, but will thicken as they cool. Let them cool uncovered for 10 or so minutes, then serve.